Systems and methods for eccentric nodule tissue acquisition

ABSTRACT

The present disclosure relates to the field of endoscopy. Specifically, the present disclosure relates to systems and methods for real-time visualization and sampling of target tissue within body passages. In particular, the present disclosure relates to a system that provides real-time visualization of eccentric pulmonary nodules, and which allows the location/orientation of a biopsy needle to be determined prior to its first actuation.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of priority under 35 U.S.C. §119 to U.S. Provisional Patent Application Ser. No. 62/431,006, filed onDec. 7, 2016, which is incorporated by reference in its entirety for allpurposes.

FIELD

The present disclosure relates to the field of endoscopy. Specifically,the present disclosure relates to systems and methods for real-timevisualization and sampling of target tissue within body passages.

BACKGROUND

Radial endobronchial ultrasound (R-EBUS) provides a minimally invasiveoption when clinical presentation indicates that tissue biopsy withinthe pulmonary passages is necessary. Conventional R-EBUS transbronchialneedle aspiration (TBNA) involves delivering a radial ultrasound probeto the target airway through the working channel of a bronchoscope,visualizing the target pulmonary nodule on R-EBUS, locking placement ofan access sheath, removing the radial ultrasound probe from the accesssheath and then blindly advancing a biopsy needle to acquire cellularmatter for cytologic evaluation. This blind sampling may often result inthe biopsy needle completely missing the target nodule. To ensure thatthe target nodule is successfully biopsied, the medical professionaltypically actuates the biopsy needle into the pulmonary tissue multipletimes while rotating the endoscope. Such repetitive biopsy needleactuations may result in a variety of negative medical outcomes, e.g.,unnecessary trauma to healthy tissues surrounding the target nodule,reduced bleeding, increased likelihood of false-negative results, andincreased procedure duration and cost. The inability to consistently andpredictably acquire biopsy samples is especially problematic foreccentric (e.g., offset) pulmonary nodules, which occur in approximately40% of all pulmonary procedures. Sampling of eccentric pulmonary nodulesrequires that either the catheter or biopsy needle is able to bend orflex within the narrow pulmonary passages.

Accordingly, various advantages may be realized by a system thatprovides real-time visualization of eccentric pulmonary nodules, andwhich allows the location/orientation of a biopsy needle to bedetermined prior to its first actuation.

SUMMARY

The present disclosure, in its various aspects, provides advantages inthe medical field, such as the field of pulmonary endoscopy, of asampling system that allows real-time visualization of eccentricpulmonary nodules, and which allows the location/orientation of a biopsyneedle to be determined prior to its first actuation. In variousembodiments, an offset biopsy needle and radial ultrasound transducerare disclosed, which may allow for accurate and efficient biopsy ofeccentric pulmonary nodule tissue.

In one aspect, the present disclosure relates to an endcap, comprising aproximal end; a distal end; a first lumen extending between the proximaland distal ends to define a first opening; and a second lumen extendingbetween the proximal end and an outer surface of the endcap to define asecond opening. The first and second lumens may be separated by avariable thickness inner wall. A thickness of the inner wall may taperdown from the distal end to the proximal end to define a ramped surfacewithin the second lumen. The ramped surface may include an angle ofapproximately 5 degrees to approximately 10 degrees relative to alongitudinal axis of the endcap. The first lumen may be configured toreceive an ultrasound transducer. The second lumen may be configured toreceive a tissue sampling element. The endcap may include a variety ofmaterials, including, but not limited to metallic or ceramic materials.

In another aspect, the present disclosure relates to a system,comprising a delivery device that includes first and second workingchannels; and an endcap comprising first and second lumens definingrespective first and second openings. A proximal end of the endcap maybe attached to a distal end of the delivery device such that the firstworking channel is contiguous with the first lumen, and the secondworking channel is contiguous with the second lumen. The first andsecond lumens may be separated by a variable thickness inner wall, inwhich a thickness of the inner wall may taper down from the distal endto the proximal end to define a ramped surface within the second lumen.The system may further include an ultrasound transducer disposed withinthe first working channel and first lumen. The ultrasound transducer mayextend distally beyond the distal end of the endcap. The system mayfurther include a tissue sampling element slidably disposed within thesecond working channel and second lumen. The proximal end of the endcapmay be attached to a distal end of the delivery device by a heat shrinksleeve disposed about an outer surface of a proximal portion of theendcap and an outer surface of a distal portion of the delivery device.A distal portion of the delivery device may include a pocket that theendcap is configured to fit within. The pocket may include a skivedopening configured to align with the second opening. The ultrasoundtransducer may be disposed within a sheath, wherein a portion of thesheath includes a radiopaque material. The radiopaque material mayinclude, for example, a strip of radiopaque material which extends alonga length of the sheath. A portion of the sheath may extends distallybeyond the ultrasound transducer. The strip of radiopaque material andthe second opening in the outer surface of the endcap may be offset byapproximately 180 degrees.

In another aspect, the present disclosure relates to a method,comprising advancing a tissue sampling system through a body passage,wherein the tissue sampling system includes a delivery device comprisingfirst and second working channels, and an endcap comprising first andsecond lumens defining respective first and second openings, wherein aproximal end of the endcap is attached to a distal end of the deliverydevice such that the first working channel is contiguous with the firstlumen, and the second working channel is contiguous with the secondlumen; imaging a target tissue with the body passage; advancing thetissue sampling element distally beyond the second opening of the endcapinto the target tissue such that a portion of the target tissue iscaptured within a lumen of the tissue sampling element; and withdrawingthe system from the body passage. The target tissue may be imaged underultrasound using the ultrasound transducer. The tissue sampling elementmay be advanced into the target tissue simultaneous with the imaging ofthe target tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting examples of the present disclosure are described withreference to the accompanying figures, which are schematic and notintended to be drawn to scale. In the figures, each identical or nearlyidentical component illustrated is typically represented by a singlenumeral. For purposes of clarity, not every component is labeled inevery figure, nor is every component of each embodiment of thedisclosure shown where illustration is not necessary to allow those ofskill in the art to understand the disclosure. In the figures:

FIG. 1 provides a cross-sectional view of a catheter endcap, accordingto one embodiment of the present disclosure.

FIGS. 2A-2B provide schematic views of the catheter endcap of FIG. 1attached to the distal end of a catheter, according to one embodiment ofthe present disclosure.

FIGS. 3A-3B provide schematic views of a tissue sampling system,according to one embodiment of the present disclosure.

FIGS. 4A-4B provide representative ultrasound images of concentric (FIG.4A) and eccentric (FIG. 4B) pulmonary nodules, according to oneembodiment of the present disclosure.

FIGS. 5A-5F illustrate the steps involved in sampling an eccentricpulmonary nodule, according to one embodiment of the present disclosure.

FIGS. 6A-6D illustrate the steps involved in sampling an eccentricpulmonary nodule, according to one embodiment of the present disclosure.

It is noted that the drawings are intended to depict only typical orexemplary embodiments of the disclosure. Accordingly, the drawingsshould not be considered as limiting the scope of the disclosure. Thedisclosure will now be described in greater detail with reference to theaccompanying drawings.

DETAILED DESCRIPTION

Before the present disclosure is described in further detail, it is tobe understood that the disclosure is not limited to the particularembodiments described, as such may vary. It is also to be understoodthat the terminology used herein is for the purpose of describingparticular embodiments only, and is not intended to be limiting beyondthe scope of the appended claims. Unless defined otherwise, alltechnical terms used herein have the same meaning as commonly understoodby one of ordinary skill in the art to which the disclosure belongs.Finally, although embodiments of the present disclosure are describedwith specific reference to real-time visualization and sampling ofeccentric pulmonary nodules, the systems and methods disclosed hereinmay be used to obtain biopsy samples from within a variety of bodylumens, including, for example, the heart, vascular system, circulatorysystem, gastrointestinal (GI) tract, stomach, esophagus, urogenitalsystem and the like. In various embodiments, the catheter endcap may besuitable for use with variety of tissue sampling tools (e.g., graspingor cutting elements) in addition to biopsy needles.

As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used herein,specify the presence of stated features, regions, steps elements and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components and/or groups thereof.

As used herein, the term “distal” refers to the end farthest away from amedical professional when introducing a device into a patient, while theterm “proximal” refers to the end closest to the medical professionalwhen introducing a device into a patient.

The present disclosure generally provides a dual-lumen catheter endcapwhich supports the side-by-side and simultaneous use of a tissuesampling element and a radial ultrasound transducer. The sloped orangled configuration of one of the lumens may provide the ability tosample eccentric nodules without requiring the tissue sampling elementto include a pre-formed curvature. The dual-lumen endcap is compatiblefor use with a radial ultrasound transducer configured to providereal-time visualization of the target pulmonary nodule whilesimultaneously indicating the location/orientation of the biopsy needlerelative to the radial ultrasound transducer prior to its firstactuation. The dual-lumen cap and radial ultrasound transducer may alsoprovide real-time visualization of the target pulmonary nodule andlocation/orientation of the biopsy needle for subsequent actuations intothe same (or different) nodule.

Referring to FIG. 1, in one embodiment, the present disclosure providesa catheter endcap 110 comprising a proximal end 112, a distal end 114and first and second lumens 116, 118 separated by a variable thicknessinner wall 122. The first lumen 116 may extend between the proximal anddistal ends 112, 114 to define a first opening 116 a. The second lumen118 may extend between the proximal end 112 and an outer surface of theendcap 110 to define a second opening 118 a. The first and secondopenings 116 a, 118 a are not limited to substantially circular andoblong shapes, respectively, but may include a variety of other shapesand/or configurations. The variable thickness inner wall 122 may taperdown from the distal end 114 to the proximal end 112 such that thesecond lumen 118 defines a ramped surface 122 a (e.g., sloped, angled,etc.). The ramped surface 122 a may include an angle of approximately 5degrees to approximately 10 degrees relative to a longitudinal axis (L₁)of the endcap 110, and may include any degree of angle therebetween. Theendcap may be unitarily formed from a variety of metallic, ceramic orhardened plastic materials, as are known in the art.

In one embodiment, an endcap of the present disclosure may be configuredfor attachment to a delivery device (e.g., catheter). Referring to FIG.2A, a delivery device 230 may include a distal portion 233 which definesa recessed portion 233 a (e.g., pocket) configured to receive the endcap210. The outer surface 220 of the endcap 210 may form an interference orfriction fit within the recessed portion 233 a sufficient to prevent theendcap from dislodging during use (e.g., within the patient). Inaddition, or alternatively, the endcap 210 may be secured within therecessed portion 233 a by a suitable weld, solder, braze, adhesive, glueand/or resin. The recessed portion 233 a may further include a skivedopening 233 b configured to align with the second opening 218 a of theendcap 210. Referring to FIG. 2B, the proximal end 212 of the endcap 210may be attached to the distal end 234 of the delivery device 230 by asleeve 235 disposed about an outer surface 220 of the endcap 210proximal portion 212 a and an outer surface of the delivery device 230distal portion 233. The sleeve 235 may cover a limited portion of thesecond opening 218 a. In one embodiment, the sleeve 235 may include aheat shrink material configured to secure the endcap 210 to the deliverydevice 230 without substantially increasing the thickness of thedelivery device or endcap. In addition, or alternatively, the sleeve 235may be secured to the delivery device and endcap by an interference fitand/or a suitable weld, solder, braze, adhesive, glue or resin.

Referring to FIG. 3A, the delivery device 330 may include first andsecond working channels 336, 338 such that when the endcap 310 issecured to the delivery device, the first working channel 336 alignswith and forms a contiguous lumen with the first lumen 316, and thesecond working channel 338 aligns with and forms a contiguous lumen withthe second lumen 318. The contiguous first working channel 336 and firstlumen 316 may be configured to receive an ultrasound transducer 340disposed within a flexible sheath 344. The sheath 344 may extenddistally beyond the ultrasound transducer 340 to protect the ultrasoundtransducer as the delivery device 330 is advanced through a bodypassage. The sheath 344 may also provide a conduit through which amedical professional may intermittently introduce a suitable fluid(e.g., isotonic saline, etc.) for consistent and reliable propagation ofultrasound energy. In one embodiment, the sheath 344 and ultrasoundtransducer 340 may be fixedly disposed within the contiguous firstworking channel 336 and first lumen 316. In another embodiment, thesheath 344 and ultrasound transducer 340 may be slidably disposed withinthe contiguous first working channel 336 and first lumen 316. In yetanother embodiment, the ultrasound transducer may include a radialultrasound probe which is rotatably disposed within the sheath 344. Thecontiguous second working channel 338 and second lumen 318 may beconfigured to slidably receive a tissue sampling element 350 (e.g.,biopsy needle). Referring to FIG. 3B, the tissue sampling element 350may be distally advanced along ramped surface 322 a of the endcap 310such that the tissue sampling element 350 deflects (e.g., bends) awayfrom a longitudinal axis of the endcap 310 upon exiting the secondopening 318 a. When the tissue sampling element 350 is actuated beyondthe distal end 314 of the endcap 310, the tissue sampling element 350and ultrasound transducer 340 are offset relative to each other byapproximately 180 degrees. Stated differently, the tissue samplingelement 350 exits the second opening 318 a at a location on the endcap310 that is directly opposite (e.g., directly above) the ultrasoundtransducer 340. Alternatively, the tissue sampling element andultrasound transducer may be offset relative to each other by an anglethat is less than 180 degree (e.g., approximately 90 degrees,approximately 100 degrees, approximately 110 degrees, approximately 120degrees, approximately 130 degrees, approximately 140 degrees,approximately 150 degree, approximately 160 degrees, approximately 170degrees), or by an angle that is greater than 180 degrees (e.g.,approximately 190 degrees, approximately 200 degrees, approximately 210degrees, approximately 220 degrees, approximately 230 degrees,approximately 240 degrees, approximately 250, approximately 260 degrees,approximately 270 degrees).

The ultrasound images of FIGS. 4A-4B demonstrate the morphologicaldifference between a concentric pulmonary nodule (FIG. 4A) that occupiesa central portion of the pulmonary passage, and an eccentric pulmonarynodule (FIG. 4B) that is disposed on a side portion of the pulmonarypassage.

Referring to FIGS. 5A-5F, in use and by way of example, a bronchoscope(not depicted) may be advanced through the trachea and into a bronchialpassage in the vicinity of a target tissue site (e.g., pulmonarynodule). The delivery device 330 (e.g., catheter) of FIG. 3A may beadvanced through and distally beyond a working channel of thebronchoscope to provide an ultrasound image of the bronchial passage. Asthe delivery device approaches the target tissue site, the ultrasoundtransducer 340 may provide an ultrasound image of the eccentric nodule 8(FIG. 5A). As illustrated in FIG. 5B, the eccentric nodule 8 may appearas a dark lesion in the upper left quadrant of the ultrasound image,relative to ultrasound transducer 340 that is identifiable as a darkcircle in the center of the ultrasound image. With the ultrasoundtransducer 340 positioned in the vicinity of the eccentric nodule 8, themedical professional may actuate (e.g., distally advance) the tissuesampling element 350 through the second opening 318 a of the endcap 310into the wall of the pulmonary passage (FIG. 5C). As illustrated in FIG.5D, the tissue sampling element 350 first appears on the ultrasoundimage after being actuated (e.g., distally advanced) beyond theultrasound transducer 340. In the event that the tissue sampling element350 does not penetrate the eccentric nodule following the firstactuation, the medical professional may retract the tissue samplingelement 350 into the endcap 310, rotate the entire delivery device 330based on the relative location of the tissue sampling element 350 andeccentric nodule 8 (FIGS. 5C-5D) to align the second opening 318 a withthe eccentric nodule 8 (FIG. 5E), and then re-actuate the tissuesampling element 350 through the second opening 318 a of the endcap 310into the eccentric nodule 8 (FIG. 5F). The tissue sampling element 350may then be retracted into the endcap 310 and the delivery device 330proximally retracted into the bronchoscope and removed from the patient.The biopsy sample of the eccentric nodule may then be removed fromwithin the lumen of the tissue sampling element 350 for cytologicevaluation. Although the tissue sampling element 350 of FIG. 5C is shownas penetrating the wall of the bronchial passage at a location that doesnot enter the eccentric nodule 8 (e.g., the target nodule is “missed”),in various embodiments the tissue sampling element 350 may be actuateddistally beyond the ultrasound transducer 340 such that the end (e.g.,sharpened point) of the tissue sampling element 350 appears on theultrasound image but does not extend into the wall of the bronchialpassage. The medical professional may then rotate the entire deliverydevice 330 to align the exposed tissue sampling element 350 with theeccentric nodule 8, and then completely or fully actuate the tissuesampling element 350 into the eccentric nodule 8. While the deliverysystem of FIG. 3A may be advantageous over conventional needleaspiration systems, it may be beneficial for the medical professional todetermine the location/orientation of a biopsy needle relative to thetarget pulmonary nodule while the biopsy needle is housed within theendcap and/or delivery device (e.g., prior to its first actuation).

Referring to FIG. 6A, in one embodiment, the delivery device of FIG. 3Amay include an ultrasound transducer 340 disposed within a flexiblesheath 344 that further includes a radiopaque material disposed in a“strip” 346 along a length of a portion of the sheath. For example, theradiopaque material may be integrally formed within the sheath 344during the extrusion process. Referring to FIG. 6B, the strip 346 ofradiopaque material may provide a radiopaque marker which is visible asa dark portion (e.g., slice) on the ultrasound image. As discussedabove, because the tissue sampling element 350 exits the second opening318 a of the endcap 310 and extends directly opposite (e.g., directlyabove) the ultrasound transducer 340, the fixed location of the sheath344 and radiopaque strip 346 allows the medical professional to identifywhere the tissue sampling element 350 will appear prior to itsactuation.

In use, and by way of example, a bronchoscope (not depicted) may beadvanced through the trachea and into a bronchial passage in thevicinity of a target tissue site (e.g., pulmonary nodule). The deliverydevice 330 (e.g., catheter), including a sheath 344 and radiopaque strip346, may be advanced through and distally beyond a working channel ofthe bronchoscope to provide an ultrasound image of the bronchialpassage. As the delivery device approaches the target tissue site, theultrasound transducer 340 may provide an ultrasound image of both theeccentric nodule 8 and the radiopaque strip 346 (FIGS. 6A-6B). Thedelivery device 330 may then be rotated such that the radiopaque strip346 and eccentric nodule 8 appear on opposite sides of the ultrasoundimage (FIG. 6C). The tissue sampling element 350 may then be actuatedthrough the second opening 318 a of the endcap 310 into eccentric nodule8 (FIG. 6D). The tissue sampling element 350 may be repeatedly retractedand actuated into the eccentric nodule depending on the amount of biopsytissue needed, without concern about surrounding healthy tissue. Thetissue sampling element 350 may then be retracted into the endcap 310and the delivery device 330 proximally retracted into the bronchoscopeand removed from the patient. The biopsy sample of the eccentric nodulemay then be removed from within the lumen of the tissue sampling element550 for cytologic evaluation.

The medical devices of the present disclosure are not limited tobronchoscopes, and may include a variety of medical devices foraccessing body passageways, including, for example, catheters,ureteroscopes, duodenoscopes, colonoscopes, arthroscopes, cystoscopes,hysteroscopes, and the like.

Finally, although the embodiments of the present disclosure have beendescribed in use with a bronchoscope, the delivery device of the presentdisclosure may be positioned within the patient in the absence of anaccompanying medical device. For example, the medical device may beintroduced into the patient through a working channel of the medicalinstrument itself.

All of the devices and/or methods disclosed and claimed herein can bemade and executed without undue experimentation in light of the presentdisclosure. While the devices and methods of this disclosure have beendescribed in terms of preferred embodiments, it may be apparent to thoseof skill in the art that variations can be applied to the devices and/ormethods and in the steps or in the sequence of steps of the methoddescribed herein without departing from the concept, spirit and scope ofthe disclosure. All such similar substitutes and modifications apparentto those skilled in the art are deemed to be within the spirit, scopeand concept of the disclosure as defined by the appended claims.

What is claimed is:
 1. A system, comprising: a delivery device comprising first and second working channels; an endcap comprising first and second lumens defining respective first and second openings; a sheath comprising a marker, the marker positioned to indicate, in an ultrasound image, a projected position of a portion of a tissue sampling element when the portion of the tissue sampling element is advanced distally beyond the second opening of the second lumen of the endcap; and an ultrasound transducer disposed within the sheath, wherein a proximal end of the endcap is attached to a distal end of the delivery device such that the first working channel is contiguous with the first lumen, and the second working channel is contiguous with the second lumen.
 2. The system of claim 1, wherein the first and second lumens are separated by a variable thickness inner wall; and wherein a thickness of the inner wall tapers down from the distal end to the proximal end to define a ramped surface within the second lumen.
 3. The system of claim 2, wherein the ramped surface includes an angle of approximately 5 degrees to approximately 10 degrees relative to a longitudinal axis of the endcap.
 4. The system of claim 1, wherein the ultrasound transducer extends distally beyond the first opening of the endcap.
 5. The system of claim 1, further comprising the tissue sampling element slidably disposed within the second working channel and second lumen.
 6. The system of claim 1, wherein the proximal end of the endcap is attached to the distal end of the delivery device by a heat shrink sleeve disposed about an outer surface of a proximal portion of the endcap and an outer surface of a distal portion of the delivery device.
 7. The system of claim 1, wherein a distal portion of the delivery device includes a pocket, and wherein the endcap is configured to fit within the pocket.
 8. The system of claim 7, wherein the pocket includes a skived opening configured to align with the second opening.
 9. The system of claim 1, wherein the marker includes a strip of radiopaque material.
 10. The system of claim 1, wherein a portion of the sheath extends distally beyond the ultrasound transducer.
 11. The system of claim 1, wherein the marker and the second opening in an outer surface of the endcap are offset 180 degrees.
 12. The system of claim 1, wherein the endcap comprises a metallic or ceramic material.
 13. The system of claim 1, wherein one or more of the first and second openings comprises an oblong shape.
 14. The system of claim 1, wherein the second lumen includes a ramped surface comprising an angle of approximately 5 degrees to approximately 10 degrees relative to a longitudinal axis of the endcap.
 15. A method, comprising: advancing a tissue sampling system through a body passage, wherein the tissue sampling system includes: a delivery device comprising first and second working channels, and an endcap comprising first and second lumens defining respective first and second openings, wherein a proximal end of the endcap is attached to a distal end of the delivery device such that the first working channel is contiguous with the first lumen, and the second working channel is contiguous with the second lumen; imaging a target tissue and at least a portion of a marker in the body passage to generate an ultrasound image, the portion of the marker in the ultrasound image indicating a projected position of a portion of a tissue sampling element when the portion of the tissue sampling element is advanced distally beyond the second opening of the second lumen of the endcap, wherein a sheath comprises the marker; advancing the tissue sampling element distally beyond the second opening of the second lumen of the endcap into the target tissue such that a portion of the target tissue is captured within a lumen of the tissue sampling element; and withdrawing the system from the body passage.
 16. The method of claim 15, wherein the target tissue is imaged under ultrasound using an ultrasound transducer.
 17. The method of claim 15, wherein the tissue sampling element is advanced into the target tissue simultaneous with the imaging of the target tissue.
 18. The method of claim 15, comprising an ultrasound transducer inserted through the second lumen to image the target tissue and at least a portion of the marker in the body passage, wherein the ultrasound transducer is disposed within the sheath comprising the marker.
 19. An apparatus, comprising: a delivery device comprising first and second working channels; an endcap comprising first and second lumens defining respective first and second openings; and a sheath comprising a marker, the marker positioned to indicate, in an ultrasound image, a projected position of a portion of a tissue sampling element when the portion of the tissue sampling element is advanced distally beyond the second opening of the second lumen of the endcap, wherein a proximal end of the endcap is attached to a distal end of the delivery device such that the first working channel is contiguous with the first lumen, and the second working channel is contiguous with the second lumen.
 20. The apparatus of claim 19, wherein a distal portion of the delivery device includes a pocket, and wherein the endcap is configured to fit within the pocket. 